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Q: Blower motor whine

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Hello. I've just replaced the blower motor (fan motor) and when I turn the air on there is a whine/hum which increases in pitch when I turn the fan setting up. Is it normal for the fan motor to rub against the blower motor housing? I noticed when I turn the fan blades manually, there is resistance against the housing. If so how cold I fix it? The part is proper size. Perhaps theres sone thing in the way or perhaps it was reassembled improperly enough to cause this. If it's normal then I'm not sure what it could be. The resistor is fine but if it isn't, is here a way to check if it's damaged or not? It looks fine. Thank you

My car has 216000 miles.
My car has a manual transmission.

A: Hello, thank you for writing in. If it is a...

Hello, thank you for writing in. If it is an aftermarket blower motor, as opposed to an OEM original dealer part, that might account for the noise. That would be my first suspicion, especially if you are sure you have otherwise installed it correctly. Aftermarket parts can often be very problematic and in many cases are dramatically different (inferior) compared to the OEM part. One way to test for a defect is to operate the fan outside of the car in free air and evaluate the noise level. If the fan is clearly noisy as well, the part is simply no good. If it is an OEM part but noisy, you might have a defective unit or you might not have installed it properly. Depending on what your circumstances are (i.e., if you end up obtaining a replacement motor) feel free to inquire further; YourMechanic is mobile and can assist you with the installation by coming to your home or office.

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